
function SDMenu(id) {

    if (!document.getElementById || !document.getElementsByTagName)
        return false;

    this.menu = document.getElementById(id);
    this.submenus = this.menu.getElementsByTagName("div");
    this.remember = true;
    this.speed = 3;
    this.markCurrent = true;
    this.oneSmOnly = false;
}

SDMenu.prototype.init = function () {

    var mainInstance = this;

    for (var i = 0; i < this.submenus.length; i++)
        this.submenus[i].getElementsByTagName("span")[0].onclick = function () {
            mainInstance.toggleMenu(this.parentNode);
        };

    if (this.markCurrent) {
        var links = this.menu.getElementsByTagName("a");

        for (i = 0; i < links.length; i++) {
            // alert(links[i]);
            if (links[i].href == document.location.href) {
                links[i].className = "current";
                break;
            }
        }
    }

    if (this.remember) {
        var regex = new RegExp("sdmenu1a_" + encodeURIComponent(this.menu.id) + "=([01]+)");
        //alert(regex);
        var match = regex.exec(document.cookie);
        //alert(match);
        if (match) {
            var states = match[1].split("");
            for (i = 0; i < states.length; i++) {

                try {

                    this.submenus[i].className = (states[i] == 0 ? "collapsed" : "");

                    // don't allow a selection to appear if a sub menu is collapsed.
                    // we see it as a single line if it's the first item in a sun menu.
                    if (states[i] == 0) {
                        mainInstance.hideSelection1(this.submenus[i]);
                    }
                   
                }
                catch (err) {                   
                }
        
            }
        }
        else {
            // failed to read from the cookie. Default to collapse all, open maps

            for (var i = 0; i < this.submenus.length; i++) {
                this.submenus[i].className = "collapsed";
            }

            this.submenus[0].className = ""; // never collapse parent 
            this.submenus[1].className = ""; // Traffic expanded
            this.submenus[2].className = ""; // Timetables expanded
            this.submenus[5].className = ""; // Business expanded
        }
    }
};

SDMenu.prototype.toggleMenu = function (submenu) {

    if (submenu.className == "collapsed") {
        this.expandMenu(submenu);

        if (this.markCurrent) {

            // only set current if we are expanding a menu with the current page in the sub menu 

            var caption = submenu.getElementsByTagName("span")[0].innerHTML;

            var links = this.menu.getElementsByTagName("a");

            for (i = 0; i < links.length; i++) {
                //alert(links[i]);

                var linkCaption = links[i].parentNode.parentNode.parentNode.getElementsByTagName("span")[0].innerHTML;
                if (linkCaption == caption) {
                    if (links[i].href == document.location.href) {
                        links[i].className = "current";
                        break;
                    }
                }
            }
        }
    }
    else {
        this.collapseMenu(submenu);
    }
};

SDMenu.prototype.hideSelection1 = function (submenu) {    

    if (this.markCurrent) {

        var caption = submenu.getElementsByTagName("span")[0].innerHTML;

        var links = this.menu.getElementsByTagName("a");

        for (i = 0; i < links.length; i++) {
            // alert(links[i]);

            var linkCaption = links[i].parentNode.parentNode.parentNode.getElementsByTagName("span")[0].innerHTML;
            if (caption == linkCaption) {

                links[i].className = "";
            }
        }
    }
};


SDMenu.prototype.expandMenu = function (submenu) {

    var fullHeight = submenu.getElementsByTagName("span")[0].offsetHeight;
    var links = submenu.getElementsByTagName("a");
    for (var i = 0; i < links.length; i++)
        fullHeight += links[i].offsetHeight;
    var moveBy = Math.round(this.speed * links.length);

    var mainInstance = this;
    var intId = setInterval(function () {
        var curHeight = submenu.offsetHeight;
        var newHeight = curHeight + moveBy;
        if (newHeight < fullHeight)
            submenu.style.height = newHeight + "px";
        else {

            clearInterval(intId);
            submenu.style.height = "";
            submenu.className = "";
            mainInstance.memorize();
        }
    }, 30);
    this.collapseOthers(submenu);
};

SDMenu.prototype.collapseMenu = function (submenu) {

    var minHeight = submenu.getElementsByTagName("span")[0].offsetHeight;
    var moveBy = Math.round(this.speed * submenu.getElementsByTagName("a").length);
    var mainInstance = this;
    var intId = setInterval(function () {
        var curHeight = submenu.offsetHeight;
        var newHeight = curHeight - moveBy;
        if (newHeight > minHeight)
            submenu.style.height = newHeight + "px";
        else {
            clearInterval(intId);
            submenu.style.height = "";
            submenu.className = "collapsed";
            mainInstance.memorize();
            mainInstance.hideSelection1(submenu);
        }
    }, 30);
};

SDMenu.prototype.collapseOthers = function (submenu) {
    if (this.oneSmOnly) {
        for (var i = 0; i < this.submenus.length; i++)
            if (this.submenus[i] != submenu && this.submenus[i].className != "collapsed")
                this.collapseMenu(this.submenus[i]);
    }
};

SDMenu.prototype.expandAll = function () {

    var oldOneSmOnly = this.oneSmOnly;
    this.oneSmOnly = false;
    for (var i = 0; i < this.submenus.length; i++)
        if (this.submenus[i].className == "collapsed")
            this.expandMenu(this.submenus[i]);
    this.oneSmOnly = oldOneSmOnly;
};

SDMenu.prototype.collapseAll = function () {

    for (var i = 0; i < this.submenus.length; i++)
        if (this.submenus[i].className != "collapsed")
            this.collapseMenu(this.submenus[i]);
};

SDMenu.prototype.memorize = function () {
    if (this.remember) {
        var states = new Array();
        for (var i = 0; i < this.submenus.length; i++)
            states.push(this.submenus[i].className == "collapsed" ? 0 : 1);

        // alert("states " + states);
        var d = new Date();
        d.setTime(d.getTime() + (30 * 24 * 60 * 60 * 1000));
        document.cookie = "sdmenu1a_" + encodeURIComponent(this.menu.id) + "=" + states.join("") + "; expires=" + d.toGMTString() + "; path=/";
    }
};